An assessment of greenhouse gas emissions: implications for the Australian cotton industry

The majority of cotton produced in Australia is exported. The Australian cotton industry must maintain product quality in order to remain globally competitive. In addition, carbon-conscious consumers need reassurance that the system used to grow the product is environmentally sustainable. The aim of the present study was to estimate greenhouse gas (GHG) emissions due to various farm inputs in three common types of cotton farming systems on the Darling Downs region, southern Queensland. Analysis revealed that GHG emissions for dryland solid-plant and dryland double-skip cotton farming systems are similar, but emissions are much higher for irrigated solid-plant cotton farming (1367, 1274 and 4841 kg CO(2)e/ha, respectively). However, if comparisons of GHG emissions are based on yield (per tonne), the positions of dryland double-skip farming and dryland solid-plant farming are reversed, but the position of irrigated cotton farming still remains as the highest GHG emitter. If the cotton industry comes under the Australian Government Carbon Pollution Reduction Scheme (CPRS) without any subsidies and preconditions, and with a carbon price of A$25/t CO(2)e, the costs borne by each system would be A$66.8/t for the irrigated cotton industry, A$39.7/t for the dryland solid-plant cotton industry and A$43.6/t for the dryland double-skip cotton industry. This suggests that irrigated cotton would be more profitable in financial terms but with heavy environmental sustainability costs.